Lug strap



March 3, 1931. J. H. cHADBouRNE LUG STRAP Filed June 27, 1929 2Sheets-Sheet l March 37 1931- .1. H. cHADBoURNE 41,795,272

v LUG STRAP Filed June 2'7, 1929 2 Sheets-Shea?- 2 /f/B r/ ffzgl jjPatented Mar. 3, 1931 UNITED STATES PATENT OFFICE o JOSEPH H.CHA'DBOURNE, OF DANIELSON, CONNECTICUT, ASSIGNOR T0 E. H. JACOBS MTG'.CO., 0F DANIELSON, CONNECTICUT, A CORPORATION OF CONNECTICUT LUG STRAPApplication led. J'une 27,

My present invention relates to lug straps for looms and moreparticularly to an improved lug strap and method of making the same.

' Lug straps as made at the present day are invariably made of one ormore pieces of ticking or duck cemented and rolled fiat and pressed fiattogether and later bent into a U shape so as to better receive thepicker stick I and to withstand the pounding that so soon destroys theusefulness of the strap. In making the prior types of lug straps it hasbeen usual to take a plurality of superimposed pieces of ticking or duckand roll the same up into an elongated roll which is pressed flat andallowed to set and is afterwards bent into a bow or U shape. This stepinthe method of manufacture, namely, of bending the lu after the fabrichas been glued and presse places an undue strain on the outermost layersof the duck or ticking and it has been found that the greatestpercentage of failures occur at the outside of the bend of the strap.

This is necessarily so as the entire strain to which the strap issubjected is placed on a relatively few of the outer layers of tickingor duck. The inner layers are wrinkled, slac and ruptured.

Such older forms of lug strap have a plug fitted in at the heel and heldin osition a rivet passing therethrough and t rough the sides of thestrap. It is impossible to force the plug into close contact with theheel and the entire strain of working comes on the rivet, with theresult that a great deal of the breakage occurs at the point .where therivet passes through the sides. This strain on the portion where therivet passes through is intensified when it is considered that the lugswill creep, that is, one side will become lon er than the other when inuse, and if the ug strap then has its position in the loom changed.I theentire strain comes on one of the side pieces only. As the older form oflug other adhesive used, had set, the relation of the various layerswith respect to each other was disturbed.

In my present invention I have devised an improved method of manufactureby which strap was bent into shape after the glue, or

1929. Serial No. 374,116.

is produced a lug strap of superior quality and 1n practicing myimproved method I form the lug strap of a plurality of layers, eachsuccessive layer being built into practically the form in which the lugstrap is to ultimately take, and during the buildmg up operationincorporate therein various short strips of reinforcing material andalso strips of material that form the rounded inner face of the lugstrap. The resultant lug strap is a structure in which each layerperforms its share of the work and the pressure and tensions beingevenly distributed, I have been able to eliminate the greater percentageof breakage, such as occurred at the bend in former types of lug straps.

Reinforcing devices, such as projections, indentations, or cords orwires act not only as a reinforcement but also serve to bind the layerstogether in such aimanner as to firmly prevent slippage of the layerswith respect to each other. Also, by building the plug in the heel I amable to dispense entirely with the use of rivets and the entire lugstrap assembly comprising the sides, heel, plug and reinforcements,becomes a single homogeneous mass. By buildingI the lug strap of aplurality of layers placed on each other in the position they willoccupy in service, there is Y no disturbance between the various layersand also the more tension placed on the lug strap in service, the closerthe various elements are brought together at the heel.

An object of my invention, therefore, is an improved method ofmanufacturing lug straps for'looms and the like.

Another object of my invention is an improved lug strap.

Referring to the drawings illustrating a preferred embodiment of myinvention and mechanism by which my improved method may be economicallypracticed;

Fig. 1 is a side elevation of a lug strap;

Fig. 2 is a plan view of Fig. 1;

Fig. 3 is a section on the line 3-3 of Fig. 1 but showing a groovesubstituted for va rib;

Fig. 4 is Fig. 2;

a section on the line 4-4 of Fig. 5 isa section on the line 5 5 of Fig.2;

Fig. 6 is a perspective view of the mandril employed in practicing myinvention;

Fig. 7 is a perspective view of a mould utilized in connectionwith Fig.6;

F-ig. 8 is a side elevation of a lug strap in position 011 a mould blocksimilar to Fig. 6, and surrounded by a mould such as is illustrated inFig. 7, and

Fig. 9 is a side elevation of Fig. 8.

Referring to the drawings, 10 designates a complete lug strap formed ofa plurality of layers of fabric or other suitable material 11, suchfabric being formed to build up a U-shape-d structure. Referring to Fi 2it will be noted that the legs of the U- Iiaped structure constitutingthe lug strap 10 are tapered, being gradually larger, moving from rightto le t in such figure, and this enlargement is made possible by theinsertion at various points of pieces of fabric 12 of less length thanthe layers of fabric 11.

Also the connecting portion of the legs ofthe lug strap 10 hasincorporated therein additional pieces 13 of fabric and also there isformed of the layers 11, fabric pieces 12, and reinforcing pieces 13, aninner ball member 14. The inner and outer faces of the legs of the lugstrap 10 have formed therein out of the fabric longitudinally arrangedribs 15, such ribs on the inner end extending as far only as the ballmember 14. I may, if it is deemed advisable, omit either the inner orthe outer, or both, of the ribs 15 and may insert in addition thereto,or in place thereof, or omit entirely, parallelly arrangedreinforcingmembers 16 which may be of cord, yarn, rawhide or metal ofany suitable character. T he various layers of fabric 11, 12, andreinforcing pieces 13 are held together by any suitable adhesive and Iam not to be limited in this regard to any particular type of adhesive.The lug strap 10 is preferably subjected during the .manufacturingoperation to pressure and after completion there is formed, adjacent theends of the legs thereof, elongated slots 17, through which may pass theusual holding bolts. In place of the reinforcing ribs 15 I maysubstitute depressed grooves 18 either on the inner or outer faces or onboth the inner and outer faces.

While the improved lug strap above described may be built by hand, Iprefer from a manufacturing standpoint to build the same with theaddition of moulding apparatus such as is shown in Figs. 7, 8 and 9, andreferring to such figures, 2O designates a mould block which may beprovided on opposite faces with longitudinally extending ribs 21, orsuch ribs may have substituted therefor longitudinally extending grooves22. Preferably the mould block 20 is of sufficient length to enable twolug straps 10 to be manufactured thereon and for this purpose I havemounted such mould block 20 on a suitable shaft 23 and mount such shaftso as to have the same rotatable in suitable bearings (not shown). Onthe ends of the mould block 2O I form depressions 24 in which the ballmember 14 of the lug strap 1() maybe formed. With such a mould block Ipreferably take a strip of fabric or other suitable material 11, Wind alayer completely around the block 20, apply adhesive to the outer faceof such layer, wind a succeeding layer, and apply adhesive after eachlayer is placed in position. At the proper times I add to the structurebeing built up on the block 20, the reinforcing layers l2, passing thesame over the ends of the block 20 and at the proper time add to thetopof each block the reinforcing members or layers 13. After a suiicientnumber of layers of fabric 11, 12, and 13 have been placed on the block20, I slide over such completed member the outer mould casings 25, suchouter mould casings being provided-on the inner faces thereof withparallelly arranged grooves 26, or with parallelly arranged ribs 27, orI may omit the same if desired. Also,`

it should be understood that at the proper time I place on thebeing-built-up structure the parallelly arranged reinforcing members 16.After the structure is built and the outermould casings laced thereon,the entire mould is placed 1n a compressing apparatus, where thebeing-built-up structure is allowed to set, after which the built-upstructure is cut apart to form a pair of lug straps, such as is shown inFigs. 1 and 2, it being understood that after this cutting operation isperformed the elongated slots 17 are cut in the side walls of the lugstrap.

It will be apparent that this method of building a lug strap insuresthat the layers of fabric 11, 12 and 13 conform to the final shape ofthe finished product and, therefore, that each layer when a lug strap isin operation is subjected to the same stress or strain. Also in this.form of lug strap all rivets are omitted, being unnecessary, andtherefore there is no danger of breakage due t0 perforating the materialunnecessarily. Being subjected to equal stresses and strains there is notendency for the outer layers 11 and 12 to break in use as is the casein former types of lug straps where a final shape is only given to4 thelug strap after the various layers are incorporated into a unitarystructure. It should be understood that in former types the inner layersare subject to compression during the manufacturing operation, while theouter layers are subject to tension and in use the breakage in ninetypercent or more cases occurs at the outer end face or at the left handend of the structure shown in Fig. 5.

By building the legs of the U-shaped structure tapered, it is possibleto use existing holders and insert material into the structure at theplace Where the strain is greatest.

I may, if it is desired, make a mould consisting of practically aplurality of elements such as shown in Figs. 6, 7, 8 and 9, arrangedside by side and form a plurality of lug straps 1() at a singleoperation and after the building and compressing opera-tions areperformed saw the combined unit into separate elements,

such as shown in Figs. 1 and 2.

Having thus described my invention what I claim as new is:

1. That improved method of manufacturing lug4 straps which ,consists informing a strip of fabric into a U-shaped form, successive layers ofmaterial thereto, applyling reinforcing material thereto as thesuccessive layers are added, incorporating the successive layers andreinforcing material into a unitary stucture by the use of adhesive.

2. That improved method of manufacturing lug straps which consists informing a strip of material into substantially U-shaped form, addingsuccessive layers thereto by the use of adhesive, applying reinforcingmaterial as the structure is built up, forming ribs on the legs of theU-shaped fabric forms, and

subjecting the built-up structure to pressure.

3. That improved method of manufacturinglug straps which consists informing a layer of fabric about a rectangular mandril so as to cause thefabric to form a substantially U-shape, adding successive layers there-vto by the useof adhesive, applying reinforcing layers of material at theproper places and times, adding reinforcing rods thereto and 'extendingparallel to the length of the legs of the U-shaped forms, yand formingreinforcing ribs on the inner'and outer faces of. the legs by means ofpressure.

4. That improved method of manufacturing lug straps which consists informing a Cit strip of material in substantially U-shaped form andpredetermined length, adding successive layers of substantially the samelength as the first layer and attaching the same to preceding layers bythe use of adhesive, applying reinforcing'material to the layers as thestructure is built up, said reinforcing material being of less lengththan the first said strip, forming ribs on the legs of the U-shapedformsout of the material of which the legs are composed and subjectingthe built up structure to pressure.

In testimony whereof, I have signed my name to this'specifcation.

JOSEPH H. CHADBOURNE.

addingv

